CT collimator and CT system including the CT collimator

Abstract

A CT collimator comprising a rotating slot part on a rotation shaft and having a plurality of blades, each blade has a slot of a different width and a radiation beam entering the collimator can only pass via a slot in one of the blades, each edge of each blade slot along a longitudinal direction has a convex curved surface structure, and in a vertical plane along a longitudinal direction, two side edges of the slot are curved, and each blade is arranged to be eccentric to the center of the rotation shaft. A CT system using the CT collimator, the detection area of the radiation rays projected to the radiation detector via the CT collimator can be maintained unchanged by adjusting the rotation angle of the blade, under the circumstance where the focus of the radiation source shifts during a CT scan.

Description

BACKGROUND TO THE INVENTION[0001]The present application relates to the field of radiograph CT, and more particularly, to a CT collimator having a single motor drive system and a radiograph CT system having the CT collimator.[0002]At present, radiograph CT systems such as X-ray CT system are widely used in various medical institutions for three-dimensional imaging of the regions of interest of the subjects to assist the clinicians to achieve an accurate medical diagnosis of the subjects.[0003]In a radiograph CT system, a radiation tube generating cone-shaped radiation beams and a detector detecting the radiation beams rotate around a rotation center, wherein the detector is disposed opposite to the radiation tube and consists of detector elements arranged in a matrix form. Projection data generated by the radiation beams transmitting through the subject are collected; based on the collected projection data, an image of the region of interest of the subject is reconstructed; and then...

AI Technical Summary

Benefits of technology

The present invention provides a CT system with a rotating slit collimator and a radiation detection area monitoring unit that can automatically adjust the collimator angle to compensate for focus shift of the radiation source during a CT scan. The collimator has multiple blades with variable slot widths and curved surfaces to ensure that the radiation beams remain at the same location on the detector, even if there is temperature change. This system allows for improved tracking of the radiation beams and eliminates the need to move other components during a scan.

Problems solved by technology

Such a collimator comprises at least two gates or cams, which are driven by at least two different motor drive systems, and hence have higher cost.

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